Field of the Invention
The invention relates in general to a computer, and more particularly to a rack server system and an auto-addressing method thereof.
Description of the Related Art
The rack server adopts high density node configuration, centralized power supply unit (PSU) management and heat dissipation system, and is further equipped with a rack management controller (RMC). The user can log on the RMC through a remote network connection to monitor the state of the rack server, such as the state of the nodes, the state of fan control, the state of PSU and the state of rack power consumption. The RMC and the backplanes are connected through an RJ45 signal line. The RMC monitors the temperature and rotation speed of the fan through the I2C device disposed on the backplanes and further communicates with the nodes through the intelligent platform management bus (IPMB). Examples of the I2C device are such as super input/output (super I/O) controllers, I/O expanders, and so on.
The rack server has limited space and can only accommodate 4 backplanes to the maximum. A backplane connects 10 nodes. Each backplane is connected to an I2C channel of the RMC by using an independent I2C bus because the address of each device on the I2C bus is unique and cannot be repeated. When the backplanes are serviced, the power supply to the 10 nodes on the backplanes will be interrupted which is very inconvenient and inflexible.